The interaction of aging and 10 years of racing on ultraendurance running performance

The aim of this study was to examine the interaction between aging and 10 years of racing in endurance runners. Race-time data from 194 runners who had completed 10 consecutive 56-km ultramarathons were obtained. The runners were either 20.5 +/- 0.7, 30.0 +/- 1.0, 39.9 +/- 0.9, or 49.4 +/- 1.0 years old at their first race. Each runner's race speed was determined for each race over the 10 years. Data were analyzed using repeated-measures ANOVA, one-way ANOVA, and independent t tests and showed that performance improved and declined at greater rates for younger runners; younger runners had a greater capacity for improvement than older runners; approximately 4 years were required to reach peak racing speed, regardless of age; it was not possible to compete at peak speed for more than a few years; and the combined effects of 10 years of aging and racing neither improve nor worsen net performance. In conclusion, these data suggest that although these runners showed similar patterns of change in race speed over a 10-year period, the extent of change in performance was greater in younger than in older runners.     

Pitfalls in portfolio planning

This paper presents an analysis and comparison of the Boston Consulting Group, McKinsey & Co., and Arthur D. Little portfolio models and a discussion of the theoretical and operational problems with the general portfolio construct. The models seem to share the goal of optimizing the firm's financial performance and the same fundamental assumptions. The strategies suggested by each model will not always be the same because of differences in the structure of the three models. Also strategic analysis of each unit is necessary to avoid the pitfalls caused by the theoretical and operational problems with the portfolio construct.     

An augmented data scoring algorithm for maximum likelihood

The expectation-maximization (EM) method facilitates computation of max¬imum likelihood (ML) and maximum penalized likelihood (MPL) solutions. The procedure requires specification of unobservabie complete data which augment the measured or incomplete data. This specification defines a conditional expectation of the complete data log-likelihood function which is computed in the E-stcp. The EM algorithm is most effective when maximizing the iunction Q{0) denned in the F-stnp is easier than maximizing the likelihood function.

The Monte Carlo EM (MCEM) algorithm of Wei & Tanner (1990) was introduced for problems where computation of Q is difficult or intractable. However Monte Carlo can he computationally expensive, e.g. in signal processing applications involving large numbers of parameters. We provide another approach: a modification of thc standard EM algorithm avoiding computation of conditional expectations.     

Putting Localism in Place: Conservative Images of the Good Community and the Contradictions of Planning Reform in England

Over the past 5 years, the UK Coalition and subsequent Conservative governments have sought to develop an agenda of localism. Recent research has evaluated how this has played out in practice. This article takes a different approach, interpreting how the language of community and place in English politics has been mobilized in reforms of the country’s planning system. We do this by tracing how conservative traditions of political thought and imagery of place were used to advance localism. This reveals a range of contradictions within the English localism agenda and highlights the wider political challenges raised by attempts to mobilize the affective and morally charged language of the local.     

The potential value of mosses for stormwater management in urban environments

Plant-based stormwater management systems such as green roofs are typically composed exclusively of vascular plants. Yet, mosses have several desirable properties that could warrant their more widespread use in green roof applications. In natural systems mosses are important primary colonizers of bare ground, and their establishment improves water storage and provides numerous soil benefits including carbon and nitrogen sequestration. Additionally, mosses often facilitate the establishment and survival of vascular plants at otherwise environmentally harsh or stressful sites. Despite their potential value, few studies have investigated the functional performance of mosses on green roofs. In this study we evaluated the establishment success and potential stormwater performance of three candidate moss species. We also directly compared the runoff and thermal characteristics of replicate moss covered green roofs to vascular planted and bare roofs. Candidate mosses had high water holding capacities, storing 8–10 times their weight in water compared to only 1.3 times for typical green roof medium. Mock-up roof sections composed of mosses and medium had delayed and reduced runoff flows relative to medium only sections, although the magnitude of these effects varied with moss species. In field trials all three mosses survived a harsh rooftop environment with limited summer irrigation, although lateral growth after one year was minimal. Green roofs planted solely with Racomitrium canescens had between 12–24% higher stormwater retention than vascular or medium only roofs. Moss cover also ameliorated temperature fluctuations on green roofs. Hourly heating rates were buffered to a similar degree (less than half that of surface temperatures) 5 cm below the surface of both moss covered and medium only roofs. In contrast, cooling under the surface of the moss roof was nearly 6 times faster than under the medium only roof. These results demonstrate the potential for mosses to be valuable components of green roofs, either in combination with vascular plants or planted exclusively.     

Responding to Self‐harm: A documentary Analysis of Agency Policy and Procedure

This paper reports on the findings of a documentary analysis of policies and procedures relating to self‐harm from a range of organisations working with young people in the UK. It identifies the extent to which policies and/or procedures relating to self‐harm are available for service providers and offers a wider understanding of the concepts of self‐harm and approaches to helping as incorporated into service guidance and delivery. It highlights the prevalence of self‐harming behaviours in a climate of stigma and the need to define appropriate and supportive agency responses from a trained staff that is both sensitive and individualised.